Adjustable boom for cranes or the like



web 13, 1951 L. R. RUSSELL 2,545,047

' ADJUSTABLE BOOM FOR CRANES OR THE LIKE Filed July 12, 1947 3 Sheets-Sheet 1 INVENTOR. [00/5 A? Ausse/l 13, 195i 1.. R. RUSSELL ADJUSTABLE BOOM FOR CRANES OR THE LIKE 3 Sheets-Sheet 2 Filed July 12, 1947 INVENTOR. Lou/5 A? /?u5$e// BY 0 VLMM w,

ATTORNEY March E3, 1951 1.. R. RUSSELL ADJUSTABLE BOOM FOR CRANES OR THE LIKE 5 Sheets-Sheet 3 Filed July 12, 1947 ATTORNEY Patented Mar. 13, 1951 UNITED STATES PATENT OFFICE 2,545,047 AEJUSTABLE BOOM FOTR '(iItAitES OR THE LIKE Louis B: Russell, Edison, ohiogassignor to Irisley Manufacturing Corporation, Indianapolis, Ind.,

a corporationof Indiana Application July 12, 1947; Serial No. 760,571

5 Claims. 1

This invention relates to machines or apparatus equipped with a boom which is mounted for vertical swinging movement upon a carriage, or the like, such, for example, as cranes and excavating machines.

Heretofore, in machines of this character, it has been an onerous-operation to vary the length of the boom. In many casesgthis necessitated that the boom be dismantled and one or more sections added or removed, depending upon whether a longer or shorter boom-was required for the particular job.- Not only has this been a time-consuming operation, but a difficult and expensive one. With a View of overcoming this problem, telescoping booms have been used to some extent, but this has required'changingi the boom hoist, as well as the'boom section supports. This-still has involved expensive work, additional equipment and skilled workmen, and, therefore, has not fully overcome the problem.

An object of this invention is to produce a Simple and efii'cient extensible boom, thelength of which can be conveniently varied Without varying the'boom hoist or the support for the boom sections.

, Another object is' to, produce an extensible'boom for cranes, excavating machines or the like, which, uponbeing' lowered to the supporting surfaceand by moving the machine, will be readily variedin length.

Other objects-and advantages-reside in details of construction, assembly and operation hereinatterdescribed, and by way of illustration butnct of limitation, an embodiment of the'invention is shown on the accompanying drawings, in which Figure l is a side elevation of an excavating machine embodying the invention;

Figure 2 is a side elevation with some-7 0i the parts broken away of the extensible boom showing the hoist and supporting cables: and'a'c'lam shell bucket suspended fromthe outer end;

I Figure 3 is a: diagrammatic plan view showing the supporting cable for the boom sections and the manner in which runs of such cable pass over sheaves-onthe boom sections-as well as-thesheave connected to the boomhoisting cable or tackle;

Figure 4 is atop plan view of the extensible boom;

p Figure '7 is an enlarged sectional view on the line-'l-l of Figure'i; V

Theillustrated embodiment of the invention comprises ail-excavating machine A which, as shown, is mounted on crawlers B, suitable machinery being provided for operating thecrawlers to enable the machine to belmove'd from place .to place. The machine has the usualturntable C supporting the operatingmach-inery and pivotally connected to asu-itable bracket [8 on the turntable is an extensibleboom D; As shown, the boom is pivoted at l i for verticalor up and down swinging movements. willlbe. hereinaftermo're fully described, theboomiis formedbf telescoping inner andouter sections, thelouter seetionbeing pivoted to the bracketsupport H] and the inner section carryingat the outer or free endisheaves 2 over which-pass cables l3 for supporting a clam shell bucket lilwhich is controlledbyacable l5 leading to asuitable drum it carried by the boom. The operation'of the clam shell-bucket as well as its control form no 113311301 thepresent invention and further description and illustration-thereof is not considered necessary. However, it should be pointed out here that the boom can be used to advantagewith other types of machines as, for example, cranes and other excavating machines such as drag line buckets, etc.

As shown particularlyonFigure 4,, the extensibleboom D has an outertelescoping section I! and an inner telescope section l8 which ismountedfor free sliding movement within the outersection.- As shown on the drawings, both-boom sections-are elongate and rectangular in cross section. Detail description of the boom-structure is not considered necessary. Suifice it-to say that each boom sectionis f-fabricated metal form constructed of angle irons and metal; bracing straps and as-particularly shownon Figured, the inner telescope boom section lil-slidesalong-and is guided by a-series of relatively'shortplates l9 which are bolted tothe inside of theouter boom section ll. A roller is is mounted on theouter end of the'telescoping boom section I 1 to militate against shearing of cables as will be readily'understood.

The inner or telescope boom section I 8 is formed along opposite sides with a series of plates 29 oppositeplates having, aligned apertures, and fixed to the inside ofeach plate- 20: inregister with the respective aperture is a reenforcing i plate 2|. Provided in the outer telescopingi boom sectionll adjacent the outer orifree endcthereof is an oppositely disposed pair ofplates 22 which are centrally apertured and provided on the in-. side is a rigid: sleeve 23. It will be manifest that by sliding the telescope. boom I8 in or out offthe telescoping boom ll, one of the-series of apertured plates may be brought into registry with the apertured plates 22 of the boom section ET. Rigidly to lock the sections in the desired position of adjustment, a rod 24 (Figure 6) may be inserted through the aligned apertures, suitable cotter keys or the like being employed for holding the rod from dropping out. In this manher, after the desired length of the boom has been achieved, the boom sections may be rigidly secured in the position of adjustment.

As will hereinafter appear, the length of the boom may be readily varied to suit the conditions of service. Conveniently, the outer end of the boom is lowered to the ground or other supporting surface, and the securing rod 24 is removed. Thereafter, by moving the machine forwardly or rearwardly, the inner boom section l8 will either slide inwardly into the telescoping boom section H, or conversely the boom section [8 will be drawn outwardly to lengthen the boom. The

boom sections i! and 18 are connected together by a single cable 25 which, in addition to providing a connection between the boom sections, also provides the connection between the boom and the hoisting device.

As shown, sheaves 26 and 27 are mounted at the inner end of the telescope boom section 18, and sheaves 28 and 29 are mounted at the outer end of the telescope boom section It. A sheave '30 is carried by a suitable bracket fastened to a block 31 forming part of the block and tackle hoist, the other block 32 being supported by a post 33 rising from the machine mounting bracket Ii and a rearwardly inclined leg 33'. The

7 cable 34 leading from the block and tackle hoist extends to a winch (not shown).

Both ends of the cable 25 are anchored to the outer or telescoping boom section ii to a cross plate which is socketed so that the ends of the cable may be embedded in lead 35 or a suitable Wedge and socket securely to hold the cable from coming loose. It will be observed that from one point of anchorage, the cable 25 extends inwardly to the sheave 21 on the telescope boom section [8, thence outwardly to the sheave 29 on the boom section l8, thence about the sheave 38 associated with the boom hoisting device, thence outwardly about the sheave 28 on the outer end of the boom section l8, thence inwardly about the sheave 26 on the inner end of the boom section it, and finally, outwardly to its other point of anchorage.

From the above description, it will be seen that the two telescoping boom sections are connected together by a single cable which also leads from the outer end of the boom to the hoisting device. This enables lengthening or shortening of the boom in a very simple manner. All that i required is that the hoisting cable 34 be paid 1 out sufiiciently to allow the outer end of the boom to rest on the ground or other supporting surface. Thereafter, by moving the machine to which the boom is connected forwardly or rearwardly, after the securing rod 24 has first been removed, the boom can be lengthened or shortened as desired. After arriving at the desired boom length, the rod 24 is again inserted through the aligned apertures in the boom sections and the boom is then ready to perform its work. It will be recognized that this structure is of decided advantage for contractors, for example,

- since they are not required to carry lengthy inf sert sections or different length boom hoist cables. Lengthening or shortening of the boom can be effected according to the above described heretofore several hours are consumed to achieve the result.

It is to be understood that numerous changes in details of construction, arrangement and operation may be effected without departing from the spirit of the invention especially as defined in the appended claims.

What I claim is:

1. Apparatus of the class described, comprising a movable carriage, a sectional boom pivotally connected at one end to said carriage, the sections of the boom being shiftable relatively to each other for lengthening or shortening same, hoisting means for said boom connected to the carriage, cable means providing a connection between the boom sections respectively and said hoisting means, and a device for rigidly securing the boom sections selectively in different positions of adjustment whereby upon lowering the free end of the boom to a supporting surface, rendering the connecting device ineffective, and imparting movement to the carriage, the length of the boom may be varied.

2. Apparatus of the class described, comprising a movable carriage, a sectional boom pivotally connected at one end to said carriage, the sections of the boom being shiftable relatively to each other for lengthening or shortening the same, hoisting cable means for said boom connected to the carriage, a single cable providing a connection between the boom sections respectively and said hoisting cable means, and a device for rigidly securing the boom sections selectively in different positions of adjustment, whereby upon lowering the free end of the boom to a supporting surface, rendering the connecting device ineifective, and imparting movement to the carriage, the length of the boom may be varied, without changing the length of the hoisting cable means.

3. Apparatus of the class described, comprising a carriage mounted for to and fro movements, a boom having a pair of telescoping sections freely slidable one within the other, a pivotal mounting for one end of the boom connected to the carriage, hoisting means on the carriage for said boom, a single cable having its ends anchored to one section and reeved about opposite end portions of said sections respectively and also reeved about said hoisting means whereby hoisting of the boom is effected by said hoisting means through said cable and the boom sections may be shifted relatively to each other without affecting said hoisting means, and a device for rigidly securing the boom sections in different positions of adjustment.

4. Apparatus of the class described, comprising a carriage mounted for to and fro movements, a boom having a pair of telescoping sections freely slidable one within the other, a pivotal mounting for one end of the boom on the carriage, hoistin means connected to the carriage for said boom, a single cable anchored at its ends to the outer end portion of the outer telescoping boom section, a pair of sheaves at the inner end of the inner boom section, a pair of sheaves at the outer end of the inner boom section, a sheave associated with said hoisting means, said single cable extending from one anchorage point about a sheave on the inner end of the inner boom section, thence about a sheave on the outer end of the inner boom section, thence about the hoisting means sheave, thence about the other sheave on the outer end of the inner boom section, thence about the other sheave on the inner end of the inner boom section to the other point of anchorage, and a device for rigidly securing the boom sections in selected positions of adjustment.

5. Apparatus of the class described, comprising a carriage mounted for to and fro movements, a boom having a pair of telescoping sections freely slidable one within the other, a pivotal about a sheave on the outer end of the inner boom section, thence about the'hoisting means sheave, thence about the other sheave on the outer end of the inner boom section, thence about the other sheave on the inner end of the inner boom section to the other point of anchorage, and a device for rigidly securing the boom sections in selected positions of adjustment.

LOUIS R. RUSSELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 495,625 Cotton Apr. 18, 1893 1,345,304 Zied June 29, 1920 20 2,365,167 Billings Dec. 19, 1944 

